外文翻譯--鎂薄板合金成形的可鍛性和可成形性的加工技術

1、<p>　　鎂薄板合金成形的可鍛性和可成形性的加工技術</p><p><b>　　摘要</b></p><p>　　金屬成型和金屬成形機床的新發(fā)展，顯示了鎂薄片具有優(yōu)秀的模鑄性能，如果工藝是在高溫下傳導。對鎂薄片成型的相應的機械性能的估價，已經在各種各樣的溫度和應變率的條件下進行的單軸向拉力的測試。鎂合金az31b、az61b的拉深測試和m1在200-25

2、0溫度范圍之間都有很好可成形性，除溫度之外，已經研究出的極限拉延比也影響模鑄的速度。產生的結果得出有可能由鎂薄片合金混合物代替?zhèn)鹘y(tǒng)的鋁和鋼薄片的結論。</p><p><b>　?、?引言</b></p><p>　　為了減少燃料消耗、一般已經有的成就是減少汽車構造的重量的，增加重量輕的物資的使用，在這個條件下、鎂合金具有對工商企業(yè)集團有特殊的使用價值，因為他們的密度

3、低，只有1.74 g／cm3。</p><p>　　不久的將來鎂合金將成為汽車零件模鑄的主要地材料。 模具鑄件技術允許放棄制造過程中復雜的幾何結構。</p><p>　　然而，這個部分的機械性能經常不能滿足機械性能的必要條件，（例如耐久強度和延性）。一種有希望能替換的材料，毫無疑問是將模鑄 工藝帶進簡便化，那部分對機械性能和細粒的微觀結構有利的沒有氣孔的制造技術。然而、一種廣泛被應用的模鑄

4、技術在鎂合金的成型的工藝中受到了限制，模鑄技術和適當的工藝參數的不完善而不得不應用（2,3）。鎂薄板金屬部件的應用對汽車車身的構造提供一個很大的潛力。通常、汽車的車身完全由板料沖壓和表現大約25%飛行器質量組成。所以，鎂薄片替代傳統(tǒng)的材料應用，將導致重量減輕的實質。</p><p>　　⒉鎂薄片的塑料性質 </p><p>　　鎂合金在室溫下顯示出可成形性的極限，這個六方晶體和孿晶體的傾向

5、是唯一的允許有限的形變。那不同地定向微晶在獨立基礎滑動平面顯示出畸形，導致一個相互的滑動障礙（４、５）。通過應用的溫度完善可以對模鑄品質進行可觀的改善！ 在200 -225溫度范圍里的可成型性的提高具有很好的可觀性（依靠合金成分） 見文獻《６》的研究。在棱形滑動面的六方形結構的熱活化性中發(fā)現了這個效果，見文獻《７》。</p><p>　　2.1成型溫度對流動應力的影響</p><p>　　

6、一種對鎂薄片畸形性質要求的測定的詳細研究的金屬的特征值同樣各向異性或流動曲線見《８、９》。 因為在這個領域里的系統(tǒng)研究表明對各種各樣的鎂合金的溫度和應變率的可塑性的大量的調查涉及金屬成型和金屬成形機床的原理的影響不是可利用的（ifum）。圖1； 顯示鎂 金屬az31b在不同溫度的流動曲線 、 顯然那應力和可能的拉緊力，大量地依靠在那成型溫度上。在2008c以上溫度范圍內流動應力的減少隨溫度的變化而的

7、變化。</p><p><b>　　3 鎂合金的拉深</b></p><p>　　為了要研究鎂薄片在不同的成型溫度的可模鍛性，在IFUM與圓筒形工具系統(tǒng)中進行拉深測試，圖3顯示在50c的溫度的拉深測試的結果。然而那az31b在低點b01：45可能的拉深比率（拉深：30mm）合金az61b和m1顯示早的破裂，使用b01：6的拉深比率，AZ31 B 顯示與 AZ61 B

8、 和 M 1 類似的 破裂，這些測試確定鎂合金的可模鍛的低點溫度。 </p><p>　　然而，調查結果顯示鎂合金在高溫的情況下有非常好的模鍛性。發(fā)現在2008c溫度下az31b的成型溫度具有最大bo的拉深比率，az61b和m1顯示鋁合金b0的最大價值提高到2：20：2.25.，AlMg4.5 Mn0.4 的比較顯示鋁合金在室溫下非常容易模鍛,鎂合金的增加的拉深比率在低點溫度與提高溫度的比較，結果表明從可拉長的測

9、試顯示那應力比率在鎂合金的機械道具的重要的影響力 。</p><p><b>　　參考文獻。</b></p><p>　　[1] H. Kehler et al., Partikelversta¨rkte Leichtmetalle, Metall Band, 49,Heft 3, 1995.</p><p>　　[2] E. Doe

10、ge, K. Dro¨der, St. Janssen, Leichtbau mit Magnesiumknetlegierungen— Blechumformung und Pra¨zisionsschmieden TechnischerMg-Legierungen, Werkstattstechnik, Band 88, Heft 11/12,1998.</p><p>　　[3] E.

11、Doege, K. Dro¨der, F.P. Hamm, Sheet Metal Forming ofMagnesium Alloys, Proceedings of the IMA-Conference on MagnesiumMetallurgy, Clermont-Ferrand, France, October 1996.</p><p>　　[4] H.J. Bargel, G. Schul

12、ze, Werkstoffkunde, VDI-Verlag GmbH,Du¨sseldorf, 1988.</p><p>　　[5] C.S. Roberts, Magnesium and Its Alloys, Wiley, New York, 1960.</p><p>　　[6] G. Siebel, in: Beck (Ed.), Technology of Magn

13、esium and Its Alloys,Hughes, London, 1940.</p><p>　　[7] N.N.: Magnesium and Magnesium Alloys, Ullmann’s Encyclopediaof Industrial Chemistry, Reprint of Articles from 5th Edition, VCH,Weinheim, 1990.</p>

14、;<p>　　[8] E. Doege, K. Dro¨der, Processing of magnesium sheet metals by deepdrawing and stretch forming, Mat. Tech. 7–8 (1997) 19–23.</p><p>　　[9] E. Doege, K. Dro¨der, St. Janssen, Umforme

15、n von Magnesiumwerkstoffen,DGM-Fortbildungsseminar, Clausthal-Zellerfeld, Oktober1998, pp. 28–30.</p><p>　　[10] L. Taylor, H.E. Boyer, in: E.A. Durand, et al. (Eds.), MetalsHandbook, 8th Edition, Vol. 4, Ame

16、rican Society of Metals,</p><p>　　Cleveland, OH, 1969.</p><p>　　Sheet metal forming of magnesium wrought magnesium wrought alloys— formabilityand process technology</p><p><b>

17、　　Abstract</b></p><p>　　New developments at the for Metal Forming and Metal Forming Machine Tools show that magnesium sheets possess excellent forming behavior, if the process is conducted at elevated

18、 temperatures. For the evaluation of mechanical properties relevant for forming of magnesium sheets, uni axial tensile tests have been carried out at various temperatures and strain rates.</p><p>　　Deep draw

19、ing tests with magnesium alloys AZ31B, AZ61B, and M1 show very good formability in a temperature range between 200 and</p><p>　　2508C. Besides temperature, the influence of forming speed on limit drawing rat

20、io has been investigated. The obtained results lead to the conclusion that it is possible to substitute conventional aluminum and steel sheets by using magnesium sheet metal wrought alloys.</p><p>　　1. Intro

21、duction</p><p>　　In order to reduce fuel consumption, general efforts have been made to decrease the weight of automobile constructions by an increased use of lightweight materials. In this framework, magnes

22、ium alloys are of special interest because of their low density of 1.74 g/cm3.</p><p>　　Presently, magnesium alloys for the use as automobile parts are mainly processed by die casting. The die casting techno

23、logy allows the manufacturing of parts with complex geometry. However, the mechanical properties of these parts often do not meet the requirements concerning the mechanical properties (e.g. endurance strength and ductili

24、ty). A promising alternative has to be seen in components that are manufactured by forming processes. The parts manufactured by this technology are characterized</p><p>　　Automotive body constructions offer

25、a great potential for the application of magnesium sheet metal components.</p><p>　　In general, the automotive body completely consists of sheet metal parts and represents a share of about 25% of the entire

26、vehicle mass. Therefore, the substitution of conventional sheet materials by magnesium sheets would lead to essential weight savings in this application.</p><p>　　2. Plastic material properties of magnesium

27、sheets</p><p>　　Magnesium alloys show a limited formability at room temperature. This results from the fact that the hexagonal crystal structure and the low tendency to twinning only allow limited deformatio

28、ns. The differently orientated crystallites only show a deformation on the individual base slip plane, which leads to a mutual slip hindrance [4, 5]. A considerable improvement of the forming qualities can be achieved by

29、 applying temperature. The considerable increase in formability that occurs in the temper</p><p>　　2.1. Influence of forming temperature on flow stress</p><p>　　A detailed evaluation of the defo

30、rmation properties of magnesium sheets requires the determination of the material’s characteristic values like anisotropy or flow curves [8, 9]. </p><p>　　Because systematic investigations in this area are n

31、ot available, extensive investigations concerning the influence of temperature and strain rate on plastic properties of various magnesium alloys were performed at Institute for Metal Forming and Metal Forming Machine Too

32、ls (IFUM). Fig. 1 displays flow curves of magnesium sheet material AZ31B at different temperatures, determined in the uniaxial tensile test according to EN 10002, part 5.</p><p>　　It is obvious that the stre

33、sses and possible strains largely depend on the forming temperature. The decrease of flow stresses in the temperature range above 2008C attributes to temperature-dependent relaxation.</p><p>　　3. Deep drawin

34、g of magnesium alloys</p><p>　　In order to investigate the formability of magnesium sheets, deep drawing tests at different forming temperatures were carried out at IFUM with a cylindrical tool system.Fig. 3

35、 shows the results of deep drawing tests at a temperature of 50C. Whereas the deep drawing of the alloy AZ31B using a low drawing ratio of b0 1:45 was possible (drawing depth: 30 mm), the alloys AZ61B and M1 showed early

36、 fracture. Using drawing ratio of b0 1:6, AZ31B showed fracture similar to AZ61B and M1. These tests con</p><p>　　However, the investigated magnesium alloys show very good formability at higher temperature ，

37、The maximum limit drawing ratio of b0 ; max 2:52 was detected for AZ31B at a forming temperature of 2008C. AZ61B and M1 show maximum values of approximately b0 ; max 2:20 up to</p><p>　　2.25. The values of

38、the aluminum alloy AlMg4.5Mn0.4 are displayed for comparison. Due to the good formability of the aluminum alloy at room temperature, the increase in limit drawing ratio with rising temperature is low compared to the magn

39、esium alloys.The results gained from the tensile tests showed the significant influence of strain rate on the mechanical properties of magnesium alloys. </p><p>　　[1] H. Kehler et al., Partikelversta¨rk

40、te Leichtmetalle, Metall Band, 49,</p><p>　　Heft 3, 1995.</p><p>　　[2] E. Doege, K. Dro¨der, St. Janssen, Leichtbau mit Magnesiumknetlegierungen</p><p>　　— Blechumformung und P

41、ra¨zisionsschmieden Technischer</p><p>　　Mg-Legierungen, Werkstattstechnik, Band 88, Heft 11/12,</p><p><b>　　1998.</b></p><p>　　[3] E. Doege, K. Dro¨der, F.P.

42、Hamm, Sheet Metal Forming of</p><p>　　Magnesium Alloys, Proceedings of the IMA-Conference on Magnesium</p><p>　　Metallurgy, Clermont-Ferrand, France, October 1996.</p><p>　　[4] H.J.

43、 Bargel, G. Schulze, Werkstoffkunde, VDI-Verlag GmbH,</p><p>　　Du¨sseldorf, 1988.</p><p>　　[5] C.S. Roberts, Magnesium and Its Alloys, Wiley, New York, 1960.</p><p>　　[6] G. Si

44、ebel, in: Beck (Ed.), Technology of Magnesium and Its Alloys,</p><p>　　Hughes, London, 1940.</p><p>　　[7] N.N.: Magnesium and Magnesium Alloys, Ullmann’s Encyclopedia</p><p>　　of In

45、dustrial Chemistry, Reprint of Articles from 5th Edition, VCH,</p><p>　　Weinheim, 1990.</p><p>　　[8] E. Doege, K. Dro¨der, Processing of magnesium sheet metals by deep</p><p>　

46、　drawing and stretch forming, Mat. Tech. 7–8 (1997) 19–23.</p><p>　　[9] E. Doege, K. Dro¨der, St. Janssen, Umformen von Magnesiumwerkstoffen,</p><p>　　DGM-Fortbildungsseminar, Clausthal-Zel

47、lerfeld, Oktober</p><p>　　1998, pp. 28–30.</p><p>　　[10] L. Taylor, H.E. Boyer, in: E.A. Durand, et al. (Eds.), Metals</p><p>　　Handbook, 8th Edition, Vol. 4, American Society of Me

48、tals,</p><p>　　ol. 4, American Society of Metals,</p><p>　　Cleveland, OH, 1969.</p><p>　　[11] K. Siegert, et al., Superplastische Aluminiumbleche — Verarbeitung</p><p>

49、　　mit numerischen Pressen, Metall, 45 Jahrgang, Heft 4, 1991.</p><p>　　[12] E.F. Emley, Principles of Magnesium Technology, Pergamon Press,</p><p>　　Oxford, 1966.</p><p>　　[13] D. S

50、chmoeckel, Temperaturgefu¨hrte Prozeßsteuerung beim Umformen</p><p>　　von Aluminiumblechen, EFB-Forschungsbericht, Nr. 55, 1994.</p><p>　　[14] H. Beißwa¨nger, Warmziehen von

51、Leichtmetallblechen, Mitteilung</p><p>　　der Forschungsgesellschaft Blechverarbeitung, Nr. 27, 1950.</p><p>　　[15] E. Kursetz, Die Anwendung von Wa¨rme bei der Herstellung von</p>&l

52、t;p>　　Blechformteilen aus Schwer Umformbaren Werkstoffen, Ba¨nder</p><p>　　Bleche Rohre, Nr. 5, 1974.</p><p>　　[16] O. Heuel, Optimierung der Werkzeugtemperatur Durch Richtige</p>